名校
解题方法
1 . 数列
是首项为1的正项数列,
,
是数列
的前n项和,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3998df04d0a8ded946c3f39d545fdc7e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b4be2164a2c67d6163faee87a10942bb.png)
A.![]() | B.数列![]() |
C.![]() | D.![]() |
您最近一年使用:0次
2022-03-24更新
|
795次组卷
|
2卷引用:黑龙江省鹤岗市第一中学2021-2022学年高二下学期第一次月考数学试题
名校
解题方法
2 . 已知正项等比数列
的前
项和为
,且满足
是
和
的等差中项,
.
(1)求数列
的通项公式;
(2)令
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06097d8a1b079ed6a402c42be3c30328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c39835887158fcba559fdfe35ebb5c63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/039e4fe671d61e59b96ee525c9df43e8.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/152e0d73ac48569b81e0b68aadfffecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
您最近一年使用:0次
2021-01-20更新
|
111次组卷
|
2卷引用:黑龙江省鹤岗市第一中学2021届高三上学期第三次模拟(12月)数学(文)试题
10-11高一下·黑龙江鹤岗·期中
3 . 等比数列{
}的前n 项和为
,已知
,
,
成等差数列.
(1)求{
}的公比q;
(2)若
-
=3,求
.
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/90971a5d37434800a94e9df6804fecdf.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/c24e0a48c49748ad8d0394ec24801d85.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/4bd4555132994faeafcbb15a814ebcb2.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/1f612af06a4544ce92bee1abb72eacf3.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/3dee0026ca324e50bfaf3bbd722b619b.png)
(1)求{
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/90971a5d37434800a94e9df6804fecdf.png)
(2)若
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/0f8fac1e49f74953a4f0c38b7dd61bdb.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/625e092473be4466906224793272d7c4.png)
![](https://img.xkw.com/dksih/QBM/2012/1/30/1570705771282432/1570705776558080/STEM/8c771f9805d64444ba7c6746d5a810b8.png)
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